.content {
  width: 500px;
  height: 300px;
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  top: 50px;
  background-color: pink;
  overflow: hidden;
}
.center {
  position: absolute;
  width: 2500px;
  height: 300px;
}
.center li {
  float: left;
  width: 500px;
  height: 300px;
  overflow: hidden;
}
.btn-left-right {
  width: 100%;
  height: 100%;
  position: absolute;
}
.btn-left-right a {
  font-size: 35px;
  width: 40px;
  height: 60px;
  top: 50%;
  transform: translateY(-50%);
  position: absolute;
  z-index: 1;
}
.btn-left-right a:first-child {
  left: 0;
}
.btn-left-right a:last-child {
  right: 0;
}
.content {
  position: relative;
}
.btu {
  width: 180px;
  height: 30px;
  position: absolute;
  top: 80%;
  left: 50%;
  transform: translateX(-50%);
}
.btu li {
  text-align: center;
  line-height: normal;
  height: 100%;
  font-size: 20px;
  float: left;
  margin-left: 20px;
  cursor: pointer;
  background-color: #000;
  color: white;
  width: 15px;
}
.nav {
  width: 100%;
  height: 200px;
  background-color: red;
}
.ai {
  width: 50px;
  height: 50px;
  position: absolute;
  z-index: 5;
}
.ai div {
  width: 20px;
  height: 20px;
  background-color: pink;
  position: absolute;
}
.one {
  transform: rotate(-150grad);
  left: 0%;
  border-radius: 0px 60%  60% 0px;
}
.two {
  transform: rotate(150grad);
  right: 35%;
  border-radius: 60% 0px 0px 60% ;
}
.three {
  left: 13%;
  top: 12%;
  transform: rotate(-252grad);
  border-radius: 0px 60% 20% 260% ;
}
.zong_xin {
  width: 100%;
  height: 100%;
}
